Can I restrict post method in flask restApi from adding another data to the database?-CodePudding

Given with my current data in db, I want to restrict the post method from adding another data to the database. What I want is restrict the post method in adding another data, and just update the existing data within the db.

Code:

    def get(self):
        predict = PredictModel.query.all()
        return {'Predict': list(x.json() for x in predict)}
    def post(self):
        data = request.get_json()
        new_predict = PredictModel(data['timelag1'],data['timelag2'],data['timelag3'],data['timelag4'],data['timelag5'])
        db.session.add(new_predict)
        db.session.commit()
        db.session.flush()
        return new_predict.json(),201

Current data in db:

  "Predict": [
        {
            "timelag1":1,
            "timelag2": 1,
            "timelag3": 1,
            "timelag4": 1,
            "timelag5": 1
        }
    ]
}

Data in db after a user entered another data:

  "Predict": [
        {
            "timelag1":2,
            "timelag2": 2,
            "timelag3": 2,
            "timelag4": 2,
            "timelag5": 2
        }
    ]
}

CodePudding user response：

I recommend reading this answer concerning how to do the database manipulation (especially the later ones): Flask-SQLalchemy update a row's information

you will need some kind of primary key or unique identifier to specify the row that you want to change - something like "id" here's some sample code which will probably work if you adapt it to your case:

instance = User.query.filter(User.id==id)
data=instance.update(dict(json_data))
db.session.commit()

num_rows_updated = User.query.filter_by(username='admin').update(dict(email='[email protected]')))
db.session.commit()